Artificial stone.



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FRITZ ROBERT LOUIS GEHRE, OF BREGENZ, AUSTRIA-HUNGARY.

ARTIFICIAL STONE.

fiPEGIFICATION forming part of Letters Tatent No. 678,726, dated July16, 1901. Application filed April 5, 1900. Serial No. 11,760, (Nospecimens.)

To a whom it may concern:

Be it known that I, FRITZ ROBERT Louis GEHRE, a subject of the Emperorof Germany, residing at Brege11z,Vorarlberg, Austria-Hi1 n gary, haveinvented certain new and useful Improvements in Artificial Stone; and Ido declare the following to be a full, clear, and exact description ofthe invention, such as will enable others skilled in the art to which itappertains to make and use the same.

The invention relates to the manufacture of artificial stone.

The magnesia cements made from magnesite and chlorates, as magnesiumchlorid and aluminium chlorid, have the bad property of being neitherWaterproof nor durable against water, nor do they resist the influencesof the weather and frost. I therefore use in place of the magnesitesmaterials which, being united with chlorates, do not have this poorquality. These are boracite or stassfurthite or magne sium borate, eachsubstance by itself or two or all of them combined with hydraulic orcaustic magnesia, or also the latter alone. To one or more of thesedifferent substances selected as desired I add fifteen percent. totwenty-five per cent.,by weigh t, of pulverized crystalline or solidcalc-spar in order to greatly increase the hardness and also at the sametime to give a great impermeability to water and durability to theweather.

Heretofore calc-spar has been used in various artificial stones,however, as happens in the Preussner patent, for example, entirely asfilling material in combination with magnesite but it is impossible togain a technical result if calc-spar is used entirely as a fillingmaterial only for magnesite, for the carbonic acid contained in itcauses a swelling or cracking of the overlaid surface orpreviously-prepared objects, While according to my practical experienceand tests the calcspar in the combination obtained by me with theabove-named materials does not have this bad property.

The dry mixtures obtained in the abovedescribed manner I bring intowatery solution of chlorids' or chlorates for example,- zinc chlorid,aluminium chlorate ammonium chlorid, magnesium chlorid, or otherssimilar, whereof I use each singly or several combined. The proportionsare governed bythe quality of the raw material and the purpose ofapplication and range from thirty per cent. to forty per cent.,byweight. As filling material for the mass I use ten per cent.,by weight,papei pu'lp after it has been prepared in the fol lowing manner: I mixthe still wet papenpulp in the finest condition with a very small partof the mixture of boracite or stassfurthite or magnesium borate and withone or more of the above-named ehlorates and with calc-spar and allowthe product so obtained to harden. After being thoroughly hardened thisprodnot is converted into a pulverized state in order to be used asfilling material in the specified manner. This process in the preparation of the paper-pulp is necessary, because the paper-pulp supplied Wetballs together in small lumps, which would form uneven soft places inthe prepared product. In order to give the ready product a marbled orany other desired appearance, the filling material (the paper-pulp) maybe colored.

Having thus fully described my invention, what I claim as new anduseful, and desire to secure by Letters Patent of the United States,is--- 1. An artificialstone composition eomprising a chlorin salt,boracite, calo-spar, and a suitable filling material, substantially asde-- scribed.

2. An artificial-stone compositiomcompris ing a chlorin salt, boracite,oalc-spar, and a filling of paper-pulp combined with a small quantity ofa ohlorin salt, substantially as de scribed.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

FRITZ ROBERT LOUIS GENRE.

'Witnesses:

JEAN GRUND, IGUAZ I'IOLZWARTH.

